Water softening and/or scale reduction filters are used for making beverages in the restaurant and service industries. Ion exchange materials, such as weak acid cation (WAC) exchange resins, are typically used to exchange hardness minerals (calcium and magnesium) from water with hydrogen or sodium. This results in water with lower scaling potential and use of such water reduces prematurely scaling and maintenance of beverage equipment, including coffee equipment.
If the WAC exchange resin removes all of the hardness minerals, however, the ability of that water to extract coffee from the coffee-beans may be somewhat compromised, and the taste of the beverage could be adversely affected. Some residual hardness in water used to make beverages is preferred and various beverages require their own hardness specification in water.
There is a need for reduction of scaling-potential of water through use of WAC resin and an adjustable bypass feature to divert some of the water from contacting the resin that would allow the end user to dial in the hardness to a desired specification. Also, there is a need for a final polishing carbon filter to remove any residual chlorine, taste and odor from the entire amount of water (both treated by the resin and diverted through the bypass). There is a need to provide a single cartridge that can adjust the amount of untreated fluid at the time of installation from the outside of the filter cartridge with a known or predictable level of by pass and re-combine it prior to post filtration with treated fluid.